Interlocking mechanism



Feb. 16, 1932; T. BRADY 1,845,904

INTERLOCKING MECHANISM Filed April 1, 1930 2 Sheets-Sheet 1 Z3 a L; *7v 1. [21b 2'2 2'2 BY ATTORNEY Feb. 16, 1932. T, BRADY 1,845,904

INTERLOGKING MECHANISM Filed April 1, 1930 2 Sheets-Sheet v 2 42M BM-4%INVENTOR FIQZ BY ATTORNEY Patented Feb. 16, 1932 UNITED STATES PATENTOFFICE THOMAS BRADY, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO OTISELEVATOR COM- PANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEYINTERLOOKING MECHANISM Application filed April 1, 1930. Serial No.440,685.

The invention relates to interlocking mechanism and particularly tointerlocking mechanism for the hatchway doors of elevator installations.

It is desirable to lock the doors, which afford access to elevatorhatchways from the corridors, in closed position in order to lessen thepossibility of in]ury to ersons who might otherwise open a door and allinto the hatch- Way or be struck by the moving car. It is also desirableto associate circuit controlling mechanisms with the locking mechanismfor each door in order to prevent movement of the car in the hatchwaywhen any door is not locked in closed position.

In some elevator installations, particularly those in which an attendantis provided in the car, it is sometimes deemed desirable to arrangethese circuit controlling mechanisms for operation to enable starting ofthe car when the door in closing reaches a predetermined point slightlyin advance of its fully closed and locked position in order to avoiddelays in operation of the car arising from awaiting movement of thedoor to fully closed and locked position.

In such arrangements there is a possibility of a prospective passengergrasping the door after it passes the predetermined point and reopeningthe door to enter the car, thus exposing himself to the danger of beinginjured by the moving car or at least delaying the car by causingoperation of the circuit controlling mechanism associated with the doorso as to stop the car.

A feature of the present invention resides in preventing reopening of ahatchway door after it has reached a predetermined point in closinguntil the door is first moved to fully closed position.

A second feature resides in preventing full reopening of a hatchway doorifthe door is left partially open, in the event that the door in closinghas been moved to a predeter mined point slightly in advance of fullyclosed position.

A third feature resides in rmitting completion of the starting circuitsfor an elevator car when the hatchway door in closing reaches apredetermined position slightly in advance of fully closed and lockedposition and in preventing interruption of these circuits as a result ofan attempt to reopen the door after it reaches this point but before thedoor is fully closed. p

A fourth feature is the provision of a toggle lever system for operatinga hatchway door and looking it in closed position in conjunction with apawl carried by one of the toggle levers for cooperating with a rack onthe hatchway wall at the side of the door opening to prevent reopeningof the door after the door in closing reaches a osition slightly inadvance of fully closed an locked position.

A fifth feature is the provision of an interlocking switch which isconnected to the locking mechanism for a hatchway door for operationthereby and which is arranged to ell'ectively perform its functions evenin the event of failure of the operating connections between the switchand the lock.

Other features and advantages will become apparent from thespecification, taken in connection with the accompanying drawingswherein one embodiment of the invention is illustrated.

In the embodiment of the invention to be described the hatchwa-y door isslidably mounted for movement relatively of the opening in the hatchwaywall through which acoess is had to the elevator car. A toggle lever ispivotally mounted on the hatchway wall at the side of the door opening.A similar toggle lever is connected at one end to the first toggle leverand its other end is pivotally connected to the door. The toggle leversassume a straight line position when the door is fully closed to lockthe door in closed position. A handle is formed on the toggle leverconnected to the door for breaking the toggle levers to unlock the doorand to open the door. A closing device connected to one of the togglelevers is operable, as the door is opened, for biasing the door toclosed position. A pawl carried by the toggle lever mounted on thehatchway wall is arranged to cooperate with a tooth of a rack mounted onthe hatchway wall atthe side of the door opening. In the event that theopening direction beyond the above mentioned predetermined point and topermit operation of the car after closing movement of the door to thispoint butprior to movement of theidoor to fully closed position in whichit is locked by the toggle levers. A link connects the door lockingtoggle levers to a switch operating member pivotally mounted on thehatchway wall. The switch operating member is connected by a link to aswitch rod and is also provided with a finger cooperating with a cam andstop on the switch rod to open and close the switch in the event ofdisconnection of the link between the switch member and switch rod. Theswitch operating member is weighted for automatically opening the switchto prevent operation of p the elevator car in the event of disconnectionof the link between the toggle levers and the switch operating member.

In the drawings:

Figure 1 is an elevation of the hatchway side of a door embodying theinterlocking mechanism of the present invention;

Figure 2 is a side view of the interlocking mechanism shown in Figure 1,the hatchway door being omitted;

Figure 3 is an enlarged view of the rack plate and pawl illustrating theposition of the pawl when the door is fully closed and locked;

Figure 4 is a view similar to Figure 3 bu showing the position of thepawl when the door is fully opened;

Figure 5 is a view similar to Figure 3 but showing the pawl in lockingengagement with the rack tooth as a result of an attempt to reopen thedoor after the door in closing has reached a predetermined point inadvance of fully closed position;

Figure 6 is an enlarged view of the interlocking switch with one of thecasing covers removed to illustrate the relation of the switch partswhen the door is closed and locked; and

Figure 7 is a view similar to Figure 6 but showing the relation of theswitch parts when the door is unlocked and opened.

Referring 'to Figure 1, the numeral 21 designates a hatchway doorsuspended from hangers 22 cooperating with a track 23 to guidethe doorin its movement transversely of the door opening. One end of a togglelever 24 'is'pivotally mounted between lugs guide pawl roller 36 25extending from a bracket 26 mounted on a plate 29 secured to thehatchway wall 27 at one side of the door opening. The other end of lever24 is pivotally connected to a similar toggle lever 28 which ispivotally mounted on the hatchway door., The toggle levers 24 and28-Wl1en in the straight line position constitute a lock for preventingopening of the door from the corridor. A handle 31 is provided on lever28 for break-' ing the toggle levers to unlock the door andforoperatingthe levers to open and close the door. 7

The toggle levers24 and 28 do not assume a straight line position tolock the door until the door is moved to fully closed position. It istherefore desirable to provide additional means effective to lockthedoor and prevent reopening thereof particularly from the cor,- ridor,when the door is moved to a predetermined point in closing or in theevent that the forward edge of the door remains positioned between thispoint and its fully closed position after the closing operation.

Referring also to Figures 2, 3, 4 and 5, a pawl 32 is providedat one endwith an opening for receiving a stud 33. Stud 33 extends throughopenings formed in the bifurcations 34 of an extension 35 of togglelever 24 and serves as a pivot pin for pawl'32. A roller 36 .is mountedat the end of pawl 32 for cooperation with a rackdesignated as a' wholeby the numeral 37. -;Rack' 37 comprisesa plate 38 having a base portion39 secured to plate 29 at the side of the door opening. Plate 38 isprovided with a slot 40 into which pawl roller 36 projects for movementas the door is opened and closed. Slot 40 is formed to provide anextension ortooth 41 for cooperating with the roller; as will bedescribed hereinafter A cam 42 formed on plate 38 extends into slot 40and divides the slot into a channel 43 between one side edge of the slotand the cam and a channel 44 between the cam and tooth .41. Channels 43and 44 will hereinafter be referred to as the opening and closingchannels, respectively. Slot 40 also has a third channel 45. Cam 42 alsoacts to in its movement in slot 40.

The casing 46 of an interlock switch designated as a whole by 47, isalso mounted on plate 29 at the side of the door opening. Referring alsoto Figures 6 and 7 ,the interlock switch comprises a pair of spacedcontacts 48 carried by conductive springs 50 which are iso is limited bythe engagement of a stop 56, formed on the rod, with boss 54.

Switch 47 is arranged to be operated as the doors are opened and closed.Rod 53 is connected by a link 57 to a weighted member 58 pivotallymounted on plate 29 adjacent casing 46. Member 58 also has a finger 60which projects into the space between stop 56 and a cam 61 on the rodfor cooperating with cam 61 and. stop 56. A link 62 is connected at oneend to member 58 and at its other end is connected to toggle lever 24.The

contacts 48 of switch 47 are connected in a control circuit for theelevator car, such as a 1 starting circuit for the car, and are arrangedto be bridged by contact 55 to permit starting of the car only when thehatchway door is locked to prevent opening thereof.

A combined door closing and checking deas vice, designated as a whole by63, is provided for moving the door toward closed position.

This device may be of the type described in applicants prior patent No.1,685,081 issued on Sept. 25, 1928, and will not be described in detailherein as reference may be had to the patent for a detailed description.The piston rod 64 of this device is connected to toggle lever 24, beingpivotally mounted on stud 33 between the bifurcations 34 of the ex- 36tension 35 of the toggle lever. Piston rod 64 is raised as the door isopened for storing energy in a spring within the casing of the de-- vice63 for moving the door toward closed position.

a: The operation is as follows: When it is desired to open the hatchwaydoor the car attendant grasps and pulls down on the handle 31.. Togglelevers 24 and 28 are thus broken to unlock the door as they move from astraight line position. Toggle lever 24 pivots upwardly about bracket 26raising pawl roller 36 from the position shown in Figure 3 into contactwith cam 42, which guides the roller into opening channel 43. As handle31 is op crated to open the door, pawl roller 36 is rai seed with togglelever 24 and moved through opening channel 43. As pawl roller 36 passesover cam 42, the upper edge of slot 40 depresses the roller intoengagement with the back of tooth 41 for guiding the roller into channel45.

Lever 24 also acts, as the door is opened, to operate closing device 63for storing energy to close the door and moves link 62 downwardly torock member 58 clockwise. Such rocking of member 58 causes link57,assisted by engagement of finger 60with cam 61 on switch rod 53, towithdraw the rod and move bridging contact 55 from between the contacts48. The arrangement is such that contact 55 is moved frombridgingrelationship with contacts 48 when the door has been opened to apredetermined point, for example four inches from its fully closedposition. As a result, switch 47 is opened to prevent operation of thecar while the door is open. When the door has been moved to its fullyopened position, pawl roller 36 is ositioned within channel 45, as shownin igure 4, and the spring of door closing device 63 is fully tensionedfor moving the door to closed position. Bridging contact 55 ispositioned out of engagement with contacts 48, as shown in Figure 7.

When it is desired to close the door, handle 31 is released and thespring of door closing device 63 acts to operate toggle levers 24 and 28to close the door. As toggle lever 24 moves downwardly about bracket 26,pawl roller 36 is moved forwardly in channel 45 toward cam 42. Togglelever 24 also acts through link 62 to rock member 58 counterclockwise.Such counterclockwise movement of member 58 causes link 57, assisted bythe engagement of finger 60 with stop 56 on switch rod 53, to move therod upwardly.

As the door approaches closed position, pawl roller 36 strikes cam 42and is guided thereby into closing channel 44 so that as the forwardedge of the door reaches a predetermined oint, for example four inchesfrom fully closed position as previously stated, the roller 36 is inchannel 44 immediately beyond the tooth 41 of rack 37. Coincidently,contact 55 bridges contacts 48, closing switch 47 to enable operation ofthe elevator car.

As the door is moved to fully closed position, pawl roller 36 continuesto be moved forwardly in channel 44 and beneath cam 42 to the positionillustrated in Figure 3, and toggle levers 24 and 28 assume a straightline position to lock the door.

After the door has been moved to or be yond the four inch position itcannot be fully reopened either from the ear or the corridor until'afterit is moved to fully closed position. In the event that a persondesiring to use the elevator car grasps door 21 to stop its closingmovement and tries to reopen the door to enter the car, after the doorhas been moved to or beyond the four inch point but not to fully closedposition, the resulting movement of toggle lever 24 causes movement ofroller 36 of pawl 32 into engagement with tooth 41 of rack 37 as shownin Figure 5, thus preventing the door from being reopened more than fourinches. The attempt to reopen the door also results in contact 55 beingmoved downwardly between contacts 48. However, contact 55 and contacts48 are so arranged that contact 55 is not moved out of bridgingengagement with contacts 48 unless the door is opened more than fourinches. As a result, the door cannot be reopened from the corridor andswitch47 remains closed to prevent stopping of the car, it in operation,as a consequence of the attempt to reopen the door. When the intendingpassenger, finding it impossible to open the door sufficiently to enterthe car, releases the door the closing device 63 acts to move the doorto fully closed position and the toggle levers straighten to lock thedoor. 7

It is to be noted that, in the event that'the door has not fully closed,the car attendant may reopen the door, as far as the four inch position,to free the apparel or effects of pas sengers, which may have beencaught between the edge'of the door and the side of the door opening.

In the event that a closing'device such as 63 is not provided forautomatically closing the door but instead the door is closed by the carattendant through manipulation of handle 31, it may happen that the carattendant might move the door toward closed position only to an extentsufficient to close switch 47 for enabling completion of the carstarting circuits. The car might then leave the floor at which the dooris located while the door remained partially open, that is with itsforward edge positioned somewhere between four inches of closed positionand the fully closed position. However, even in such cases the doorcannot be reopened from the cor ridor sufiiciently to permit access tothe hatchway nor to open switch 47, and as a consequence stop the car ifit is in operation. An attempt to open the door beyond the four inchpoint would result in causing the roller 36 of pawl 32 to engage thetooth 41 of rack 37, thus preventing further movement of the door andopening of switch 47, as previously described.

The arrangement of the means for operating switch 47, when toggle levers24 and 28 are operated to unlock and open the door, is such that theswitch is operated even in the event of the failure of the one or moreof the operating connections between the switch and the toggle levers.For example, if the fastening means connecting the member 58 to rod 53through link 57 should become disconnected, the cooperation of finger 60with cam 61 on rod 53 would effect opening of the switch as the door isunlocked and opened and the cooperation of finger 60 with stop '56 onrod 58 would effect closing of the switch as the door is locked andclosed. In the event that the fastening means connecting link 62 tomember 58 or to toggle lever 24 should become disconnected, member 58would be moved clockwise by gravity and act through link 57, or finger60 and cam 61, to immediately open switch 47, thus preventing operationof the car until the defective parts are repaired. 1 7

It is to be noted that after the door in closing has been moved to apredetermined point in advance of fully closed position the pawl andrack cooperate to prevent reopening of the door from the corridor untilthe door has been fully closed. Thus, the pawl and rack act to lessenthe possibility of a prospective passenger being injured as a resiilt ofattempting to open the door,when it is nearly closed. When the door isfully closed the toggle levers act to prevent opening of the door fromthe corridor.

Itis also to be noted that the interlocking switch is arranged to beoperated before the door is fully closed and locked, thus lesseningdelays in operation of the car. As the interlocking switch is arrangedto be locked in operated condition when the door in closing reaches apredetermined point in advance of fully closed position it cannot bereopened until the door has been fully closed. As a result, an attemptto open the partially closed door does not effect reopening of theinterlocking switch and thereby delay the car 1101' interfere withthefunctioningof the switch as a safety device.

Furthermore the 1 construction and arrangementof the operating means forthe interlocking switch insures the desired oper ation of the switchunder all conditions.

Although the interlocking switch has been described as operated uponmovement of the door in either direction to a point located apredetermined distance from iully closed position, it is to beunderstood'that the interlocking switch may be arranged to be opened onunlocking of the door or on movement of the door from fully closedposition, and closed only upon movement of the door to, or locking ofthe door'in, fully closed position.

While the pawl and rack locking device is particularly adapted for usewith. a toggle lever system for locking and operating the door, it mayalso be employed in association with other types of door operating orlocking devices. The interlocking switch and its operating means alsoare adaptable for use with other types of door locking devices.

As many changes could be 'made in the above construction and manyapparently Widely different embodiments of this invention vcould be madewithout departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limit ingsense.

7 hat is claimed is:

1. In combination with a closure; operating means for said closure; astationary rack;

and a pawl carried by said operating means for engaging said rack toprevent reopening of said closure beyond a predetermined point inadvance of fully closed position, after said closure has passed saidpoint in closing, until said closure is first moved to fully closedposition.

2. In combination with a closure; a toggle lever connected to saidclosure; a second toggle lever connected at one end to said first togglelever and pivotally mounted at its other end adjacent the opening closedby said closure, said toggle levers assuming a straight line positionfor locking said closure when the closure is fully closed; means forbreaking said toggle levers to unlock said closure and for operatingsaid closure; a rack mounted adjacent the opening closed by saidclosure, said rack being provided with a and for operating said closure;a rack mounttooth; and a pawl carried by said second toggle lever forengaging said tooth to prevent movement of said closure in the openingdirection beyond a predetermined point in advance of fully closedposition, after the closure has passed said predetermined point 1nclosing, until said closure is first moved to fully closed position.

3. In combination with a closure; a toggle lever connected to saidclosure; a second toggle lever connected at one end to said first togglelever and pivotally mounted at its other end adjacent the opening closedby said closure, said toggle levers assuming a straight line positionfor locking said closure when the closure is fully closed; means forbreaking said toggle levers to unlock said closure and for operatingsaid closure; a rack mounted adjacent the opening closed by saidclosure, said rack being provided with a tooth; a pawl carried by saidsecond toggle lever for engaging said rack tooth to prevent movement ofsaid closure in the opening direction beyond a point at a predetermineddistance from fully closed position, after the closure has been moved tosaid point in 010s ing, until said closure is first moved to fullyclosed position; and means for raising said pawl and maintaining it outof engaging relation with said rack tooth when the closure moved in theopening direction from fully closed position.

4. In combination with a door; a lever pivotally mounted adjacent theopening closed by said door, said lever being operable upon movement ofsaid door; means for moving said door to its opened and closedpositions; a pawl carried by said lever; and a stationarg rack plateprovided with a tooth, said rac plate being also provided with a slotfor guid- 1mg said pawl to cause its engagement with said tooth to locksaid door against opening beyond a predetermined point in advance offully closed position in the event that, subsequent to closing movementof said door to said point but prior to movement of saiddoor to fullyclosed position, said door is moved toward open position.

In combination with a door; a lever pivotally mounted adjacent theopening closed by said door, said lever being operable upon movement ofsaid door to open or closed position; a rack plate mounted adjacent theopening closed by said door, said rack plate being provided with a slot;a pawl carried by said lever; a roller on said pawl, said rollerextending into said slot and being movable determined point in advanceof ully closed position in the event that, subsequent to closingmovement of the door to said predetermined point but prior to movementof the door to fully closed position, said door is moved toward openposition.

6. In combination with a door; a lever pivotally mounted ad'acent theopening closed by said door, said lever being operable upon movement ofsaid door to open or closed position; a rack late mounted adjacent theopening closed y said door, said rack plate being provided with a slot;a pawl carried by said lover; a roller on said awl, said rollerextending into said slot an being movable therein on operation of saidlever when the door is opened or closed; a rack tooth on said late, saidrack tooth extending into said slot 'or engagement by said pawl rollerto lock said door against opening beyond a predetermined point inadvance of fully closed position in t is event that, subsequenttoclosing movement of the door to said predetermined point but prior tomovement of the door to fully closed position, said door is moved toward0 en position; and means for preventing loc ing engagement of said pawlroller with said rack tooth when the door is moved from fully closedposition.

7. In combination with a door; a lever pivotally mounted adjacent theopening closed by said door, said lever being operable upon movement ofsaid door to open or closed position; a rack plate mounted adjacent theopen ing closed by said door, said rack plate being provided with aslot; a pawl carried by said lever; a roller on said pawl, said rollerex tending into said slot and being movable therein on operation of saidlever when the door is opened or closed; a rack tooth on said late, saidrack tooth extending into said slot or engagement by said pawl roller tolock said door against opening beyond a predeterminedpoint in advance offully closed po' sition in the event that, subsequent to closingmovement of the door to said predetermined point but prior to movementof the door to fully closed position, said door is moved toward openposition;and a cam on said plate, said cam extending into said slot forengagement by said pawl roller to guide said pawl roller away fromlooking engagemcnt with said rack tooth when said door is moved fromfully closed position.

8. In an elevator installation; a hatchway, one wall of said hatchwaybeing provided with a door opening; a sliding door for closing saidopening; a toggle lever pivotally mounted on said door; a second togglelever pivotally connected at one end to said firsttoggle lever andpiv-otally mounted at its other end on the hatchway. wall at one side ofthe door opening, said toggle levers assuming a straight line position,when the plate mounted at said one side of said door opening, said rackplate having a slot; a pawl carried by said second toggle lever; aroller on said pawl, said roller extending into said slot and beingmovable therein as the door is unlocked, opened or closed; a rack toothon said plate, said tooth project ing into said slot for engagement ysaid pawl roller to lock said door against reopening beyond apredetermined point in advance of fully closed position in the eventthat, subsequent to closing movement of said door to said predeterminedpoint but prior to movement of said door to fully closed position, saiddoor is moved toward open position; and a cam on said plate projectinginto said slot for guiding said roller in its movement in said slot,said cam acting as the door is unlocked to guide said roller to preventlocking engagement thereof with said tooth as said door is moved fromfully closed position and acting on closing move ment of said door tosaid predetermined point to guide said roller into position for engagingsaid tooth to prevent said reopening of the door. s

9. In an elevator installation; a hatchway door; means for locking thedoor in closed position; a switch; means connecting said switchto saidlocking means to cause said switch to be closed when the door is locked;and means for baising said switch to open position, said biasing meansacting to open said switch in the event of disconnection of said switchfrom said locking means. 10. In an elevator installation; a hatchwaydoor; means for locking the door in closed position; a switch; a switchoperating member connected to said locking means; means connecting saidswitch operating member to said switch; and means cooperating with saidoperating member to efiect the operation of said switch in the event offailure of said connecting means.

11. In combination with a closure; a switch; means for causing saidswitch to be closed when the closure in closing reaches a point at apredetermined distance from fnlly closed position; and means forpreventing the reopening of said switch and also the reopening of saidclosure beyond said point, after said closure has passed said point inclosing, until said closure is first moved to fully closed position.

12. In combination with a door; a switch; means for causing said switchto be opened when said door in opening reaches a point a predetermineddistance from fully closed position; means for causing said switch to beclosedwhen the door in closing reaches said point; and means forpreventing the reopening of said switch and also reopening of said doorbeyond said point, after said door has passed said point in closing,until said door is first moved to fully closed position.

13. In combination with a closure; a switch; means for causing saidswitch to be closed when the closure in closing reaches a point at apredetermined distance from fully closed position; means for operatingsaid door; a stationary rack; a tooth on said rack; anda pawl carried bysaid operating means for engaging said tooth to prevent reopening ofsaid switch, after the switch is closed when the door passes said pointin closing, until said door is first moved to fully closed position.

.14. In an elevator installation; a hatchway door; means for locking thedoor in closed position; a switch associated with said looking means; aswitch rod operable to open and close said switch; an operating memberfor said switch rod; means for connecting said operating member to saidlocking means; a link connecting said operating member to said switchrod; means for operating said locking means to lock or unlock said door,said operating means, on operation to lock and unlock said door, actingthrough said locking means, said connecting means, said switch operatingmember, and said link to opcrate said switch rod for respectivelyclosing and opening said switch; a cam on said switch rod; a stop onsaid switch rod; and a finger on said operating member for cooperatingwith said cam for opening said switch on unlocking of said door and forcooperating with said stop to close said switch on locking of said door,in the event of disconnection of 1iaid link from said switch rod or saidmem- 15. In an elevator installation; a hatchway door; means for lockingthe door in closed position; a switch associated with said lookingmeans; a switch rod operable to open and close said switch; an operatingmember for said switch rod; means for connecting said operating memberto said locking means; a link connecting said operating member tosaidswitch rod; means for operating said looking means to lock or unlocksaiddoor, said operating means, on operation, to lock and unlock said door,acting through said looking means, said connecting means, said switchoperating member and said link to operate said switch rod forrespectively closing and opening said switch; a cam on said switch rod;a stop on said switch rod; a finger on said operating member forcooperating with said cam for opening said switch on unlocking of saiddoor and for cooperating with .3

said stop to close said switch on locking of said door, in the event ofdisconnection of said link from said switch rod or said member; meansfor operating said door; a stationary rack; a tooth on said rack; and apawl carried by said locking means for en gaging said tooth to preventreopening of said switch, after the switch is closed when the doorpasses said point in closing, until said door is lirst moved to fullyclosed position.

16. In an elevator installation; a hatchway door; means for locking saiddoor in closed position; a switch associated with said locking means,said switch comprising a casing, a pair of spaced contacts in saidcasing, and a bridging contact for engagin said contacts to connect themelectrica ll a switch rod guided for movement in sai casting, said rodbeing operable to move said contact out of and into bridging engagementwith said contacts to respectively open and close said switch a boss onsaid casing; a stop on said rod for engaging said casing to limit themovement of said rod on operation thereof to close said switch; a cam onsaid rod; a weighted operating member for said switch rod pivotallymounted on said hatchway wail: a link connecting said switch rod to saidmember: a link connecting said member to said door locking means; meansfor 0 erating said locking means to lock or an ock said door, saidlocking means, on operation, acting through said switch operating memberand said links to move said switch rod to close or open said switch; anda finger on said switch operating member, said finger cooperating withthe cam on said switch rod to move the rod for opening said switch onunlocking of said door and cooperating with said stop on said rod tomove the rod for closing said switch on locking of the door, in theevent of disconnection of said first mentioned link from said switch rodor said switch operating member.

17. In an elevator installation; a hatchway; one wall of said hatchwayhaving a door opening; a door for said opening; a toggle lever pivctalli' connected to said door; a second toggle lever pivotally connected atone end to said first toggle lever and pivotally mounted at its otherend on said hatchway "all at one side of the door opening; said togglelevers acting to lock said door when closed; a switch associated withsaid toggle levers, said switch comprising a casing; a pair of spacedcontacts mounted in said casing, and a bridging contact adapted to beinterposed between and in engagement with said contacts for connectingthem electrical- 1y; :1 switch rod guided for movement in said casing,said switch rod being operable to move said. contact out of and intoengagement with said contacts to respectively open and close saidswitch; a boss on said casing; a stop on said rod for engaging said bossto limit the movement of said rod on operation thereof to close saidswitch; a cam on said rod; a switch operating member pivotally mountedon the hatchway wall at said one side of the door opening; means forconnecting said switch operating member to said toggle levers; a linkconnecting said switch rod to said member for movement thereby; meansfor operating said toggle levers to unlock and open said door, saidtoggle levers, upon operation to unlock and o en said door, actingthrough said connecting means, said member and said link to causemovement of said switch rod to open said switch upon movement of saiddoor to a predetermined point from closed position; means for operatingsaid toggle levers to close said door, said toggle levers, uponoperation to close said door, acting to move said switch rod to closesaid switch when said door in closing reaches said predetermined point;a rack mounted on the hatchway wall at said one side of the dooropening; a pawl carried by said second toggle lever for engaging saidrack to prevent opening of said switch after said door in closingreaches said predetermined point, in the event said door is subsequentlymoved toward open position prior to movement thereof to fully closedposition; and a cam for raising said pawl to prevent locking enga ementthereof with said rack when said oor is unlocked and moved from fullyclosed position, thereby permitting opening of said switch after saiddoor is unlocked and moved from fully closed position.

In testimony whereof, I have signed my name to this specification.

THOMAS BRADY.

